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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="move.move_algorithms"></a><a class="link" href="move_algorithms.html" title="Move algorithms">Move algorithms</a>
</h2></div></div></div>
<p>
      The standard library offers several copy-based algorithms. Some of them, like
      <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span></code> or <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">uninitialized_copy</span></code>
      are basic building blocks for containers and other data structures. This library
      offers move-based functions for those purposes:
    </p>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">O</span><span class="special">&gt;</span> <span class="identifier">O</span> <span class="identifier">move</span><span class="special">(</span><span class="identifier">I</span><span class="special">,</span> <span class="identifier">I</span><span class="special">,</span> <span class="identifier">O</span><span class="special">);</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">O</span><span class="special">&gt;</span> <span class="identifier">O</span> <span class="identifier">move_backward</span><span class="special">(</span><span class="identifier">I</span><span class="special">,</span> <span class="identifier">I</span><span class="special">,</span> <span class="identifier">O</span><span class="special">);</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F</span><span class="special">&gt;</span> <span class="identifier">F</span> <span class="identifier">uninitialized_move</span><span class="special">(</span><span class="identifier">I</span><span class="special">,</span> <span class="identifier">I</span><span class="special">,</span> <span class="identifier">F</span><span class="special">);</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F</span><span class="special">&gt;</span> <span class="identifier">F</span> <span class="identifier">uninitialized_copy_or_move</span><span class="special">(</span><span class="identifier">I</span><span class="special">,</span> <span class="identifier">I</span><span class="special">,</span> <span class="identifier">F</span><span class="special">);</span>
</pre>
<p>
      The first 3 are move variations of their equivalent copy algorithms, but copy
      assignment and copy construction are replaced with move assignment and construction.
      The last one has the same behaviour as <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">uninitialized_copy</span></code>
      but since several standand library implementations don't play very well with
      <code class="computeroutput"><span class="identifier">move_iterator</span></code>s, this version
      is a portable version for those willing to use move iterators.
    </p>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="string">"movable.hpp"</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">move</span><span class="special">/</span><span class="identifier">algorithm</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">cassert</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">aligned_storage</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>

<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
<span class="special">{</span>
   <span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">ArraySize</span> <span class="special">=</span> <span class="number">10</span><span class="special">;</span>
   <span class="identifier">movable</span> <span class="identifier">movable_array</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">];</span>
   <span class="identifier">movable</span> <span class="identifier">movable_array2</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">];</span>
   <span class="comment">//move</span>
   <span class="identifier">boost</span><span class="special">::</span><span class="identifier">move</span><span class="special">(&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array</span><span class="special">[</span><span class="number">0</span><span class="special">]);</span>
   <span class="identifier">assert</span><span class="special">(</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
   <span class="identifier">assert</span><span class="special">(!</span><span class="identifier">movable_array</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>

   <span class="comment">//move backward</span>
   <span class="identifier">boost</span><span class="special">::</span><span class="identifier">move_backward</span><span class="special">(&amp;</span><span class="identifier">movable_array</span><span class="special">[</span><span class="number">0</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">]);</span>
   <span class="identifier">assert</span><span class="special">(</span><span class="identifier">movable_array</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
   <span class="identifier">assert</span><span class="special">(!</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>

   <span class="comment">//uninitialized_move</span>
   <span class="identifier">boost</span><span class="special">::</span><span class="identifier">aligned_storage</span><span class="special">&lt;</span> <span class="keyword">sizeof</span><span class="special">(</span><span class="identifier">movable</span><span class="special">)*</span><span class="identifier">ArraySize</span>
                         <span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">alignment_of</span><span class="special">&lt;</span><span class="identifier">movable</span><span class="special">&gt;::</span><span class="identifier">value</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">storage</span><span class="special">;</span>
   <span class="identifier">movable</span> <span class="special">*</span><span class="identifier">raw_movable</span> <span class="special">=</span> <span class="keyword">static_cast</span><span class="special">&lt;</span><span class="identifier">movable</span><span class="special">*&gt;(</span><span class="keyword">static_cast</span><span class="special">&lt;</span><span class="keyword">void</span><span class="special">*&gt;(&amp;</span><span class="identifier">storage</span><span class="special">));</span>
   <span class="identifier">boost</span><span class="special">::</span><span class="identifier">uninitialized_move</span><span class="special">(&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">],</span> <span class="identifier">raw_movable</span><span class="special">);</span>
   <span class="identifier">assert</span><span class="special">(</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
   <span class="identifier">assert</span><span class="special">(!</span><span class="identifier">raw_movable</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
   <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
<span class="special">}</span>
</pre>
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<div class="copyright-footer">Copyright © 2008-2024 Ion Gaztanaga<p>
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        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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